DE3150514C2 - - Google Patents

Description

The invention relates to a photographic recording material with improved antistatic properties, the one Plastic carrier, at least one photographic photosensitive Emulsion layer on one side of the support and an antistatic layer on the other side of the carrier contains.

Photographic recording materials are generally prepared by coating an electrically insulating Plastic carrier with a photographic photosensitive Emulsion layer and optionally applied thereto Antihalation layer and / or overcoat layer. The back of the support can optionally with be provided a backing layer.

In recent years, the techniques of manufacture have become photographic recording materials considerably improved, especially as regards the speed of the coating and tailoring the photographic materials As. Also the speed of handling photographic materials in photographing and the transport speed of photographic Recording materials during development have become strong elevated.

In the production and use of photographic recording materials Therefore occurs an increasing contact friction between the photographic materials themselves or between them and other materials used for enrichment electrostatic charges leads.

It is known that the formation of electrostatic charges on photographic recording materials,  that dust is attracted, which causes various problems brings. Also, with appropriate amount of electrostatic Charge a spark discharge occur, leading to the formation unwanted static marks leads.

In order to eliminate these problems, it has already been suggested the consideration of such photographic recording materials antistatic by using polymeric Electrolytes or surface-active compounds. Their effectiveness depends strongly on the moisture content of the environment, d. H. at high moisture content is the produced electrical conductivity sufficient to the unwanted dissipate electrostatic charges, while at low Moisture content of the electric generated in this way Conductivity is insufficient in many cases. also the problem arises that the antistatic equipped Backing layer of the photographic material the storage absorbs moisture and on the underlying Surface of the photosensitive layer adheres to what leads to handling problems and quality losses.

Previously used for the antistatic equipment polymeric Electrolytes and surface-active compounds with low molecular weight are generally water-soluble and are therefore used in developing the exposed photographic Solved recording materials so that they together with the other substances contained in the developer solution lead to undesirable sludge formation, the unevenness in the development.

Also the proposal to provide a carbon black dispersion layer both to avoid halation and to prevent an electrostatic charge, has become in practice not proven, because this carbon black dispersion layer during development of the photographic material is removed and after development antistatic properties thus lost.  

According to a proposal in DE-AS 31 14 627 it is possible the antistatic properties of photographic materials to improve by using fine particles of various crystalline metal oxides which dispersed in a binder, in the antistatic layer incorporated on the back of the photographic support become. Thus it is possible, the antistatic properties photographic recording materials of the above To improve construction, but these are not enough more the requirements that have increased today and more makes the resistance of the antistatic layer tacky Wishes open in damp surroundings.

The object of the invention was therefore a photographic recording material to provide, which further improved which also has antistatic properties Change in the moisture content of the environment during storage and by the treatment of the exposed photographic Recording material in a developer solution is not affected and its antistatic layer, too high moisture content of the environment does not become sticky.

It has now been found that this object is achieved by a photographic recording material comprising a plastic carrier, at least one photographic photosensitive emulsion layer on one side of the carrier and an antistatic layer on the other side of the carrier, which is characterized in that
the antistatic layer contains a binder and fine particles of at least one crystalline metal oxide selected from ZnO, TiO₂, SnO₂, Al₂O₃, In₂O₃, SiO₂, MgO, BaO and MoO₃ or a composite oxide thereof, wherein the metal oxide particles contain a dopant or oxygen deficient sites and a volume resistivity of at most 10⁷ Ω · cm, and a hydrophobic polymer layer is formed on the antistatic layer.

The photographic material of the present invention is characterized by excellent antistatic properties regardless of whether the moisture content of the environment is low or high, and moreover is the invention Recording material resistant to stickiness in a humid environment.

Preferred embodiments of the photographic invention Recording material are in the subclaims 2 to 8 described.

The fine particles of crystalline metal oxide or composite Oxides, as used herein, exhibit a volume resistivity of 10⁷ Ω · cm or less and preferably 10⁵ Ω · cm or less.

The grain size (i.e., the largest cross-sectional dimension) of these Particle is typically in the range of 0.01 to 0.7 microns and preferably 0.02 to 0.5 μm.

These fine particles can be prepared by various methods as described, for example, in JP-A-1 43 430/81 are described in more detail. Typical examples of such production methods fine particles are

• 1. a method of producing fine metal oxide particles are made by burning and then in the presence of various Atoms (dopants) are treated in the heat are used to increase the electrical conductivity,
• 2. A process in which the production of fine metal oxide particles by burning as in 1. in the presence of dopants to increase the electrical conductivity is performed, and
• 3. a method of producing fine metal oxide particles by burning as in 1. the concentration Oxygen in the atmosphere is reduced to "oxygen deficient sites" to introduce into the crystal structure.

Preferred examples of dopants for use in methods 1 and 2 above are Al and In for ZnO; Nb and Ta for TiO₂; and Sb, Nb and halogen elements for SnO₂. In general, a combination of a metal oxide and a dopant one lower or higher valency than the metal of the metal oxide (eg, a combination of ZnO (Zn ²⁺ ) and Al (Al ³⁺ ) and a combination of SnO ( SN ⁴⁺ ) and Sb (Sb ³⁺ or Sb ⁵⁺ )) are particularly preferred.

The amount of the dopant added is preferably in the range of 0.01 to 30 mol%, and more preferably at 0.1 to 10 mol%.

The amount of the conductive metal oxide particles according to the invention are used, is preferably in the range from 0.05 to 20 g / m² and more preferably from 0.1 to 10 gsm.

Binder for fine particles used to achieve an antistatic or electrically conductive layer according to the invention can be used, include cellulose esters, such as cellulose nitrate, cellulose triacetate, cellulose diacetate, Cellulose acetate butyrate and cellulose acetate propionate, homo- and copolymers of vinylidene chloride, vinyl chloride, styrene, Acrylonitrile, vinyl acetate, alkyl acrylate, vinyl pyrrolidone; soluble polyesters; polycarbonates; and soluble polyamides. In the dispersion of the fine particles, dispersing solutions, such as those based on dispersants Contain titanium or silane. also may be crosslinking agents for binders, surface-active Agents and electrolytes (eg sodium phosphate) added become.

Examples of titanium-based dispersants are coupling agents based on titanium, as described for. In US-A  40 69 192, 40 80 353 and Plenact (trademark for a Product of Ajinomoto Co., Inc.).

Examples of silane-based dispersants are vinyltrichlorosilane, Vinyltriethoxysilane, vinyltris (β-methoxy ethoxy) silane, γ-glycidoxypropyltrimethoxysilane and γ- Methacryloxy-propyltrimethoxysilane. These connections are commercially available as "silane coupling agent", for example from Shin-Etsu Chemical Industries, Ltd.

Binder cross-linking agents that can be used include epoxy-based crosslinking agents, isocyanate-based, Isothiocyanate base and aziridine base.

To achieve the desired electrical conductivity For example, the electroconductive fine metal oxide particles dispersed in a binder and applied to a support or it may be after application of a subbing treatment on the support a dispersion of electric conductive metal oxide fine particles in a binder be applied.

Carriers that may be used include those z. Cellulose triacetate, cellulose acetate butyrate, cellulose acetate propionate, Polyethylene terephthalate, polyethylene naphthalate, Polycarbonate, polystyrene, polyethylene or Polypropylene-coated paper.

In addition, according to the invention, a hydrophobic polymer layer is used on the antistatic or electrically conductive Layer formed.

The hydrophobic polymer layer applied according to the invention can be prepared by applying a hydrophobic polymers in the form of a solution in one organic solvent or an aqueous latex.  

The amount of hydrophobic polymer applied is preferably at 0.05 to 1 g / m², calculated as dry weight.

Hydrophobic polymers used in the invention may include, for. As cellulose esters, such as nitrocellulose and cellulose acetate; Vinyl-based polymers, such as polyvinyl chloride, Polyvinylidene chloride and polyvinyl acrylate; and organic solvent-soluble polyamides and polyesters.

The hydrophobic polymer layer may, if desired Lubricants are added, for. B. organic carboxylic acid amides, as described in JP-A-79 435/80 for their lubricity properties to rent. It can also matting agents be added.

The coating of the antistatic or electrically conductive Layer with the hydrophobic polymer layer can after usual techniques are performed, such. B. by Roll application, air knife or slot die coating, Gravure application, bar coating and curtain coating.

The photographic material of the present invention Optionally, an adhesive layer, an antihalation layer, an intermediate layer and a surface protective layer in addition to at least one photosensitive Layer on the photosensitive layer side of the support respectively.

The adhesive layer used here can be made are made using copolymers based on Vinylidene chloride as described, for example, in JP-A- 1 35 526/76 and US-A-31 43 421, 35 86 508, 26 98 235 and 35 67 452, copolymers based on diolefin (eg. Butadiene) as described, for example, in JP-A-1 14 120/76  and US-A-3615556, copolymers containing glycidyl acrylate or Glycidyl methacrylate, as described, for example in JP-A-58 469/76, polyamide-epichlorohydrin resins, as described, for example, in JP-A-24 923/73, maleic anhydride copolymers as described in JP-A-39 536/75.

A preferred example of a photosensitive layer is a silver halide emulsion layer. examples for useful silver halides include silver chloride, silver chlorobromide, Silver iodobromide and silver chloride iodide bromide.

Various additives, as usually in photographic Emulsions are used, for example chemical sensitizers, antifoggants, surface-active Agents, protective colloids, hardeners, polymer latices, Color couplers, markers and sensitizers Dyes can also be used according to the invention, such as in Research Disclosure, Vol. 176, p 22-28 (December, 1978).

The interlayer, the antihalation layer and the surface protective layer are also not subject to any special Restrictions and can be made using various additives, such as those in the aforementioned Research Disclosure publication are described.

The process for producing the photographic emulsions and the methods for applying various photographic Layers on the support are also not subject special restrictions and can be performed for example, as in the aforementioned research Disclosure publication described.  

A photographic material of the invention For example, in the form of a color negative film, a color reversal film and a black and white photographic film available.

The following examples serve to further explain the Invention.

example 1

A mixture of 65 parts by weight of tin IV chloride hydrate and 1.5 parts by weight antimony trichloride was in 1000 parts by weight Ethanol dissolved, forming a uniform solution. Subsequently, a 1 N aqueous solution of sodium hydroxide added dropwise to the uniform solution until the pH of the resulting solution 3 reached so as to Coprecipitate of colloidal tin IV oxide and antimony oxide to create. The co-precipitate thus obtained was  then allowed to stand for 24 h at 50 ° C, to achieve a reddish brown colloidal precipitate.

The reddish brown colloidal precipitate was removed by centrifugal separation separated. To excess ions (i.e., chloride ion), water was added to the Precipitation was added, and it was a centrifuge separation performed. This procedure was three times to remove the excess ions carried out.

To 1000 parts by weight of water, 100 parts by weight added to the colloidal precipitate from which the excess Ions were removed. The mixture was sprayed in a kiln kept at 650 ° C was used to obtain fine bluish particles with an average particle size of 0.15 μm (largest cross-sectional dimension).

A mixture with the following formulation was 5 h using a paint shaker (Commercial product of Toyo Seizai Seisakujo) to achieve a dispersion dispersed.

Parts by weight electrically conductive fine particles 200 Salan F-310 (vinylidene chloride-based copolymer, commercial product of Asahi Dow Co., Ltd.) 10 methyl ethyl ketone 150

Using the dispersion thus prepared was a coating solution having the below shown Formulated.  

Parts by weight dispersion 15 Salan F-310 3 Methyl ethyl ketone (MEK) 100 cyclohexanone 20 m-cresol 5

The coating solution thus prepared was placed on a 100 μm thick polyethylene terephthalate film applied at a dry coat weight of 1.3 g / m² and dried at 130 ° C for 2 min.

On the thus prepared layer was further Coating solution with the formulation shown below in a dry coating amount of 0.2 g / m² applied and dried for 1 min at 130 ° C.

Parts by weight Cellulose triacetate 1 methylene chloride 60 ethylene dichloride 40 erucamide 0.001

The layer thus prepared is hereinafter referred to as Backsheet called.

On the opposite side of the carrier was a conventional silver halide emulsion for microphotography applied first after an adhesive layer was applied.

The surface resistance of the backing layer was with a measuring device for the insulation resistance  determined (model VE-30, commercial product of Kawaguchi Denki Co., Ltd.) to 7 × 10⁸ Ω at 25 ° C and 25% relative humidity. Became the backsheet in contact with the photographic emulsion layer brought and under a load of 2 kg / 10 cm² at 50 ° C and 80% relative humidity during Allowed to stand for 12 h, no adhesion occurred.

Example 2

It was a dispersion of electrically conductive finer Particles prepared in the same manner as in Example 1.

Using the dispersion thus prepared was a coating composition shown below Formulated.

Parts by weight dispersion 15 Salan F-310 3 MEK 70 methanol 30 cyclohexanone 20

The coating composition thus prepared was applied a 140 μm thick cellulose triacetate film carrier applied in a dry coating amount of 2 g / m² and dried at 120 ° C for 3 min.

On the thus prepared layer was further Coating solution applied with a formulation, as shown below, in a dry coating amount  of 0.3 g / m², and dried at 120 ° C for 2 min.

Parts by weight cellulose diacetate 10 acetone 240 methanol 480 Silica (average grain size 1 μm) 0.1

A comparative sample was prepared according to Example 2 of JP-A-7 763/80 (corresponding to DE-A- 29 26 832) method described. This means First, a solution with the following formulation prepared, applied in the form of a layer and dried.

On the thus prepared layer was a dispersion of 10 parts by weight of cellulose diacetate and 0.1 part by weight fine silica particles (average grain size 1 μm) in a mixed solvent of 240 parts by weight of acetone and 480 parts by weight Methanol applied.

The surface resistance of the film thus obtained was measured at 25 ° C and 25% relative humidity.  The results are shown in the table below.

table

From the above table it can be seen that the Surface resistance of the sample that has been coated with the fine particles of tin oxide-antimony composite Oxide, even after the development processing was hardly changed.

Example 3

Using the same electrically conductive Fine parts as in Example 1 was a dispersion prepared with the formulation shown below by shaking for 3 h using the Paint shaker as in Example 1.

Parts by weight Electrically conductive fine particles 200 cellulose diacetate 5 acetone 150

Using the dispersion thus prepared was a coating solution having the below shown Formulated.

Parts by weight dispersion 7 cellulose diacetate 1 acetone 70 methanol 30

The coating solution was applied to a cellulose triacetate film of 135 microns thick, and dried in a dry coating amount of 1.5 g / m².

On the thus prepared layer became a solution applied with the formulation shown below, which was then dried, in a Dry coating amount of 0.2 g / m².

Parts by weight cellulose diacetate 1.5 acetone 30 methanol 70

On the opposite side of the so applied Layer was applied an adhesive layer and a conventional silver halide color emulsion layer applied to the adhesive layer for production a photographic photosensitive film.

Was the backing layer of the resulting film with a nylon roller at 25 ° C and 25% relative humidity rubbed, so there were no static marks.  

On the other hand, a sample without electrically conductive fine particles the same above test subjected to static markings.

Example 4

A mixture of the formulation shown below was subjected to ultrasound application for 10 minutes, to form a homogeneously dispersed Solution.

Parts by weight zinc oxide powder 100 10% aqueous solution of Al (NO₃) ₃ · 9 H₂O 5 water 100

After drying this dispersed solution for 1 hour at 110 ° C, it was sintered for 5 minutes at 600 ° C under 1.33 × 10 ^-4 mbar (1 × 10 ^-4 Torr) to obtain an electroconductive zinc oxide powder having a specific Resistance of 2 × 10 2 Ω · cm. The zinc oxide powder was crushed by a ball mill to obtain fine particles of 0.3 μm in average particle size.

A mixture of the following formulation was 1 h dispersed by means of a paint shaker to obtain a dispersion.  

Parts by weight Electrically conductive zinc oxide fine particles 55 nitrocellulose 5 MEK 320

To the resulting dispersion was added 60 parts by weight Acetone and 60 parts by weight of methanol were added, followed by stirring was to obtain a coating solution.

The thus prepared coating solution was applied to a 127 μm thick cellulose triacetate film carrier applied in an amount of 20 ml / m² and 10 min dried at 120 ° C.

On the thus prepared layer was further Coating solution with the following formulation applied in an amount of 10 ml / m² and dried.

Parts by weight cellulose diacetate 1 acetone 100 methanol 60 behenic 0.01

The layer thus prepared is hereinafter referred to as Backsheet called.

On the opposite side of the carrier was a conventional silver halide emulsion layer for microphotography applied after first applying a gelatin adhesive layer was applied.

The surface resistance of the backing layer was  3 × 10¹⁰ Ω at 25 ° C and 10% relative humidity, with excellent antistatic properties.

Claims (8)

Photographic recording material comprising a plastic support, at least one photographic photosensitive emulsion layer on one side of the support and an antistatic layer on the other side of the support, characterized in that
the antistatic layer contains a binder and fine particles of at least one crystalline metal oxide selected from ZnO, TiO₂, SnO₂, Al₂O₃, In₂O₃, SiO₂, MgO, BaO and MoO₃, or a composite oxide thereof, wherein the metal oxide particles are dopants or oxygen deficient contain and have a volume resistivity of at most 10⁷ Ω · cm, and
a hydrophobic polymer layer is formed on the antistatic layer. 2. Photographic recording material according to claim 1, characterized in that the metal oxide is um ZnO and the dopant is Al or In. 3. Photographic recording material according to claim 1, characterized in that the metal oxide is TiO₂ and the dopant is Nb or Ta. 4. Photographic recording material according to claim 1, characterized in that the metal oxide is um SnO₂ and at the dopant to Sb, Nb or a halogen element is. 5. Photographic recording material according to any one of claims 1 to 4, characterized in that the antistatic Coat the dopant in an amount of 0.01 to Contains 30 mol%. 6. Photographic recording material according to claim 5, characterized in that the antistatic layer is the dopant in an amount of 0.1 to 10 mol%. 7. Photographic recording material according to one of the claims 1 to 6, characterized in that the antistatic Layer the metal oxide particles in an amount of 0.05 to 20 g / m² contains.   8. Photographic recording material according to claim 7, characterized in that the antistatic layer is the metal oxide particles in an amount of 0.1 to 10 g / m².